Professor Erica Wanless

Career Summary

Biography

I work within the Discipline of Chemistry which sits within the School of Environmental & Life Sciences. I arrived at the University of Newcastle as a lecturer in Chemistry in December 1996 after a two year postdoc at the University of Otago in New Zealand. While employed at the University of Newcastle I have enjoyed the privilege of overseas sabbatical periods at the Universities of Sussex (UK), Bordeaux (France), Sheffield (UK), Durham (UK) and the Technical University of Berlin (Germany) together with a JSPS fellowship at the Osaka Institute of Technology (Japan). In 2013 I was promoted to Full Professor. In 2015 I was appointed to the Editorial Board of the journal Advances in Colloid and Interface Science.

Research ExpertiseI am an active researcher in both fundamental and applied colloid and surface chemistry. I have built an international reputation for my contributions to the nanometre-scale understanding of the solid-liquid interface in the presence of surfactant or polymer molecules. I was one of the first researchers to use soft-contact atomic force microscopy (AFM) to reveal detail of the lateral structure of adsorbed surfactant layers on the molecular scale. Through this I have developed highly specialised skills in soft-contact AFM imaging in water. By combining measurements of adsorption kinetics and adsorbed amounts, in 2003 we published the most thorough understanding of surfactant adsorption kinetics to date. In the last decade I have performed extensive fundamental research on the behaviour of stimulus responsive polymer molecules and polymeric colloids adsorbed at the solid-aqueous solution interface (funded by the Australian Research Council). Additionally, I have applied my fundamental knowledge & skills to a variety of industrial research problems including projects concerned with mining emulsion explosives, water-based paints, powder coatings, plastic solar cells, mineral flotation, emulsions & foams.

Teaching ExpertiseI teach in an average of five 10cp courses per year to all undergraduate years from level 1000 through to 3000 in the form of lectures, tutorials and laboratory sessions. These are predominantly in Physical, Colloid or Surface Chemistry

Administrative ExpertiseIn 2012 I served on the national ERA Research Evaluation Committee for Physical, Chemical and Earth Sciences. I was the Assistant Dean Research Training in the Faculty of Science & Information Technology 2009-2010. I have an outstanding track record of leadership and national service to the Australian Colloid and Surface Science community including membership of 5 conference organising committees since 2003 & national secretary from 1999-2009. I was Chair of the Royal Australian Chemical Institute Colloid and Surface Science Division from 2011-2012. I undertake a range of research assessment roles including reviewer for the top international journals in colloid and interface science, regular PhD thesis examiner and ARC Discovery grant assessor (IntReader).

CollaborationsThe nature of my research lends itself to collaboration, a mode of research that I particularly enjoy, whether it be with colleagues at this university, elsewhere in Australia and indeed internationally. I have an excellent record of collaborative research coupled with successful research higher degree supervision. In the past decade I have collaborated with the following scientists: Prof. Steve Armes (University of Sheffield) Dr Steve Edmondson (University of Manchester) Dr Syuji Fujii (Osaka Institute of Technology) Prof. Regine von Klitzing (Technical University of Berlin) Dr Seher Ata (University of New South Wales) Dr Stuart Prescott (University of New South Wales) and at this University with Dr Grant Webber, Prof. Graeme Jameson, Prof. Geoffrey Evans, Dr Roberto Moreno-Atanasio, Prof. Rob Atkin, Dr Clovia Holdsworth

Qualifications

PhD (Surface Sciences), Australian National University

Bachelor of Science (Chemistry)(Honours), Australian National University

The stability of capillary-pinned bubble pairs covered with hydrophobized particles in aqueous solutions of 1-pentanol or methyl isobutyl carbinol (MIBC) was studied using high-sp... [more]

The stability of capillary-pinned bubble pairs covered with hydrophobized particles in aqueous solutions of 1-pentanol or methyl isobutyl carbinol (MIBC) was studied using high-speed cinematography. Glass particles were first rendered hydrophobic by covalently bonding a linear alcohol onto the solid interface to achieve a specific hydrophobicity (i.e. contact angle of 43Â° measured with the captive bubble on a treated wafer) and effectively avoid the presence of any mobile hydrophobizing surfactant. The resistance to coalescence of the bubbles was measured at different frother concentrations and for various initial bubble interfacial areas covered by particles; with particle coverage not exceeding the contact region between the bubbles.Frother molecules were shown to delay the coalescence of bubbles whereas particles were not present in a sufficient quantity at the interface of the bubbles to provide steric stability. However, in some cases in the presence of MIBC, the particles were believed to act as means of transportation for the frother molecules to the surface of the bubbles thus forcing the local relaxation of the interface, which improved bubble stability. The coalescence of two bubbles released energy causing a rapid motion of the interface. This motion was sufficient to expel a fraction of the attached particles from the interface. The addition of frother, and of particles in some cases, increased the dampening of the oscillatory motion generated by bubble coalescence. In general, damped bubble oscillations were associated with a reduced quantity of particles detaching from the bubble. Although particles were observed to dampen the oscillation of the bubble, they were not as effective as the frother molecules in reducing the detachment of particles upon bubble coalescence. This finding is believed be of relevance for industrial applications such as froth flotation.

A 3D Discrete Element Method simulation model for a single bubble was developed in order to investigate the capture of hydrophobic particles. The bubble was considered stationary ... [more]

A 3D Discrete Element Method simulation model for a single bubble was developed in order to investigate the capture of hydrophobic particles. The bubble was considered stationary at the centre of the working space. Particle-particle and particle-bubble contacts were simulated using a linear spring-dashpot model. Gravitational, buoyancy, drag and hydrophobic forces were taken into account. The hydrophobic force was estimated through a single exponential decay law which depends on a preexponential parameter K and a decay length Â¿ It was observed that when k was less than 10 nm, the number of the particles that were collected was independent of the strength of the hydrophobic force. In contrast, for values of k within the range of 10-500 nm, the capture efficiency increased significantly with the strength of the hydrophobic force and Â¿ We have also demonstrated how these two parameters affect the particle trajectory around the bubble and thus produce a significant difference in particle collection when the strength and range of the hydrophobic force were varied.